Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
danh tai » doanh tai, dinh tai, hanh tai
canh tay » canh tac, thanh tay, anh ta
nang dau » hang dau, xang dau, nang du
tai cua » thai cua, tai cuc, tri cua
va danh » va dinh, va dan, va hanh
nam luc » nang luc, nhan luc, nam thuc
dau hoi » cau hoi, dai hoi, dan hoi
cua tre » cua te, cuu tre, cua triet
luc va » duc va, tuc va, loc va

You may be able to get more results by adjusting your search query.

• If you are trying to use Boolean operators, they must be ALL CAPS: su ((sach y) OR (((xach tay) OR (canh tay)))) nang dau hoi. hieu van nam luc va danh tai cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su ((sach y) or (((xach tay) OR (canh tay)))) nang dau hoi. hieu van nam luc va danh tai cua tre~".
• Adding a wildcard symbol may retrieve word variants: su ((sach y) or (((xach tay) OR (canh tay)))) nang dau hoi. hieu van nam luc va danh tai cua tre*.